The invention relates to a top cover box for motor vehicles of the type which is lined on its walls and its bottom with covering that has water-repellent properties, and which is provided with an outflow aperture in a low-lying region of the bottom, the covering having a downslope in the bottom region which conducts water to the outflow aperture.
Such a top cover box with lining is in use, for example, in the SL convertible series of Mercedes-Benz AG, and is thus known.
In this known top cover box, the lining consists of individual sheets of needled felt which, after being cut to size, are bonded flat on the bottom and walls of the top cover box, adopting the shape of the surfaces which support them.
Although the top cover box is covered by means of a lid at its upward-facing aperture, which lid is swung up only in order to open or close the top cover, it is nevertheless designed as a so-called wet space. This design serves the purpose of removing water which has entered the top cover box as rapidly as possible to the outside, so that a permanently damp environment cannot develop in the top cover box, which would be disadvantageous for the corrosion resistance of the painted sheet metal parts and would favor the undesirable formation of mould on the needled felt sheets and/or the top cover.
The entry of water into the top cover box may occur not only as a consequence of leaks but also because the top cover is lowered into the top cover box while still wet with rain.
In order to permit rapid removal of water from the known top cover box, the bottom thereof has a continuous forward downslope which runs into funnel-shaped recesses on both sides of the top cover box, each of which defines an outflow aperture. Moreover, the needled felt sheets are impregnated with a water-repellent substance, as a result of which absorption of the water by the needled felt sheets is prevented.
Because of the functional principle of water removal, the structural design possibilities for the top cover box in the region of the bottom thereof are substantially restricted.
This applies to the shaping of the bodywork panel itself forming the bottom of the top cover box, which must offer a continuous downslope at each point of the bottom. Moreover, no fittings must be attached to the bottom of the top cover box which would partially impede the complete outflow of the water.
An object of the invention is further to develop a top cover box of the generic type so that structural freedom of design for the top cover box bottom is distinctly increased without disadvantageous effects on the removal of water from the top cover box.
This object is achieved, according to the invention, by providing an arrangement wherein the covering of the top cover box is combined to form an insert encompassing walls and a bottom, which insert is of dimensionally stable and watertight design, wherein a groove-like recess is let into the bottom of the insert which has a downslope leading to the outflow aperture, and wherein the bottom of the insert comprises a large-format surface region with a downslope extending transversely to the longitudinal extent of the recess and towards the latter. In the region covered by the insert, the water removal towards the outflow is determined exclusively by the bottom of the insert, provided with a suitable downslope, so that the top cover box bottom of the bodywork can be designed as desired, apart from any necessary support bearing points. Thus a partially fissured sheet metal structure can be provided, as may be desirable, for example, for reasons of rigidity. Also, lines such as, for example, cables or even hydraulic lines, if appropriate with assigned hydraulic units, can readily be attached directly to the top cover box bottom, or perforations or the like can be provided, since no influence is exerted thereby on the water removal. If, for example, only a rear part of the top cover box is lined with the insert and the outflow apertures are at the front in the lateral legs of the top cover box, then the downslope to the outflow apertures in the rear part of the bottom of the insert and in front thereof--between insert and outflow--can be determined by the lateral top cover box bottom.
The two-level division of the water outflow through the insert bottom, moreover, permits a downslope in large format surface regions which can also run in the opposite direction to the downslope of the channel-shaped recess. As a result, with good utilization of structural space, a sufficient downslope can be provided. Furthermore, the position of the outflow aperture can be determined in accordance with design aspects.
If the top cover box is very extensively lined with the insert, or if the outflow aperture or a plurality of outflow apertures are in the rear region of the top cover box, the outflow aperture is covered by the insert, as a result of which the downslope must be provided exclusively by the bottom of the insert.
In order to prevent drops of water diverted by the insert from reaching the top cover box bottom, the downslope of the recess preferably ends in a pipe connector piece which projects downwards from the underside of the insert bottom and extends into the outflow aperture of the top cover box bottom.
An outflow of water from the insert which is free of blocking-up is ensured if the pipe connector piece is molded to the bottom of the insert at least over part of its bottom length.
Expediently, an outflow aperture is arranged on both sides of the vehicle in the top cover box, since as a result of this the flow paths on the bottom of the insert can be shorter, so that better utilization of the structural space can be achieved as compared with the single outflow aperture, with a predetermined downslope.
By adapting the top cover box to cover concepts of a known type and optimizing the hollow volume of the top cover box, a backward-directed downslope can prevail in the top cover box, but at the same time a downslope away from the middle of the top cover box to its sides can be present. In this case, the downslope area of the insert bottom can advantageously be surrounded by a conducting channel which consists of the groove-shaped recess in the insert bottom and has a forward-directed downslope on part of its lateral lengths.
In order to conform to varied requirements, the insert preferably consists of a multi-layer molding with a watertight barrier layer of plastic.
Such a molding can be economically produced as a three-layer laminate whose outer layers, surrounding the central plastic layer, consist of textile material. Materials which have proved suitable are a particularly moldable synthetic fibre non-woven as an outer layer lying on the top cover box and a needled felt material as the outer layer which remains visible, this combination of materials being known per se for lining bodywork areas.
Because of the dimensional stability of the molding it can be reliably connected to the top cover box by a plurality of spot-type connecting means, it being possible for the spot-type connecting means to be provided in the conveniently accessible upper edge region of the walls.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.